Thread: Up the Ramp
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Unread 10-03-2003, 11:57
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Jim Meyer Jim Meyer is offline
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My GUESS is that you are runnig too high of a gear ratio. If it is a speed controller not giving you full power, (and the fact that you are using a gear ration of 6 to 1) your design is marginal as to whether it has enough torque to get you over the ramp.

Some quick calculations 8.5*PI()/12*5500/6/60 show you would be going 34 ft/sec at the motor's free speed. I'm guessing you are always running at half that or below. No matter what your speed controllers are doing, increasing your gear ratio will help. Even if you double your gear ratio to 12:1 you should still travel at speeds in excess of 15 ft/sec (crazy fast) and still have twice as much torque.

My true recommendation would be to get your gear ratio in the neighborhood of 25:1 at a minimum if you are not shifting gears.
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